Method of weaving fabrics for tires.



E. HERKNER. v METHOD 0F WEAVING FABRIOS PoR TIRES.

APPLIOATION FILED 00T, 18,1907.

- Patented June 1, 1909.

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ERNST HERKNER, OF OBERSOHNEWEIDE, NEAR BERLIN, GERMAN-Y, ASSIGNOR TO PAUL HANSEN, OF HANOVER, GERMANY.

METHOD OF WEAVING FABRICS FOR TIRES.

Specification of Letters Patent.

Patented .Tune 1, 1909.

Application filed October 18, 1907. Serial No. 397,997.

To all wlzomtt may concern:

Be it known that I, ERNsT HERKNER, head workman, a subject of the King of Prussia and Emperor of Germany, residing at 44a idlilhelminhofstrasse, Oberschneweide, near Berlin, Germany, have invented certain new and useful Improvements in Methods of Weaving Fabrics for Tires, of which the following is a specification.

The present invention has for its object a process for the manufacture of the well known U-shaped tires reinforced by an arched woven fabric insertion, passing through the cover in the form of a continuous helix of two or more layers. Such curved fabric insertions have heretofore been made by varying the tension of the warp threads of an ordinary fabric having only a single layer. The fabric curved by the different tensions of the warp threads was stretched in a fiat form for even shedding in the loom by exterior pressure exerted on the fabric by press-rollers between which the fabric passed. By this method of stretching the fabric the formation of puckers and the like which interfered with an even shedding were not avoided sufliciently. On the other hand it is well known in the manufacture of tubes to stretch the tube in a flat form by interposing between its walls a spreader which stretches the fabric by interior pressure, thus securely avoiding the formation of puckers. The tubes made by such manufacture were not adapted for the manufacture of covers with fabric insertion in the form of a continue ous helix having a plurality of layers. The present invention possesses the advantages obtained by combining these two methods of manufacture.

According to this new invention a tube is formed, as described above, by varying the tension of the warp threads and then this tube is slit longitudinally in order to render possible the formation of the helix referred to above having a U-shaped or semi-circular cross section. If the tension of the warp threads is so varied also in the lower material that this tension is increased from the middle portion to the edges as is the case in the upper material, two U-shaped helices of a curvature suitable for the manufacture of the helical insertion will be obtained at the same time by separating the material from the up per at the edges.

The invention is diagrammatically illustrated in the accompanying drawing, in which:

Figure l is a longitudinal section through a cover having a U-shaped continuous fabric insertion of the well-known type. Fig. 2 is a cross section on the line A-B Fig. l. Fig. 3 is a perspective view of an ordinary woven tube. Fig. 4 is the outer part of the tube shown in Fig. 3. Fig( 5 is the inner part of the tube shown in Fig. 3. Fig. 6 is a perspective view of a tube for obtaining two suitable fabric insertions at the same time.

The rubber cover is designated by the reference letter a in Figs. l and 2. Through this rubber cover passes the fabric insertion in the form of a helix U-shaped in cross-section and having the different layers b, c, d.

Tf the woven tube Fig. 3 is slit up along the curved lines E-F, there is obtained an outer part E (Fig. 4), in which the middle warp thread L, M is the longest, whereas the warp threads E, F at the edges are the shortest. This part e has just the form suitable for the manufacture of the helix t, c, d Figs. l and 2. There is also obtained an inner part f (Fig. 5) in which the middle warp thread N, O is the shortest and the warp threads E, F at the edges are the longest warp threads. Therefore, this part f has not a suitable form for the manufacture of the helix b, c, d. For avoiding the disadvantage thus entailed by the loss of the part f the tension of the warp thread in the lower material is also regulated in such a manner that this tension is increased from the middle warp thread N, O to the edge-warp threads E, F. Thereby two layers e and e1 of the fabric are obtained, which ft one into the other as clearly shown in Fig. 6. lf this double fabric is slit up at the edges E, F, two fabric insertions of the suitable curva ture are obtained.

The weaving process for the manufacture of curved fabric insertions is described for example in the American Patent No. 504883 and 505949, so that it may here be assumed to be known.

What T claim and desire to protect by Letters Patent of the United States is:

l. The method of manufacturing a curved fabric insertion for U-shaped outer covers of tires, which consists of weaving a tube and imparting different tensions to the warp threads during the weaving, the greatest tension being applied to those threads situated on diametrically opposite sides of said tube,

and the tension on the intermediate warp threads subjected to constantly decreasing tensions, and slitting the tube longitudinally along the warp threads under greatest tension.

2. The process of manufacturing a curved fabric insertion for U-shaped outer covers of tires, which consists in weaving a tube with the warp threads situated in the middle of the top half and lower half of the tube longest, and the intermediate threads progressively shorter in a direction away from said middle threads so that the lower half of said tube will be curved in the same direction as the upper half of said tube.

3. The process of manufacturing a fabric for insertion in the outer covers of tires, which comprises weaving a tube, imparting, during the weaving operation, different tensions to threads runninglongitudinally ofthe tube, and dividing the tube longitudinally whereby two strips similarly curved transversely are obtained.

4. The process of manufacturing a fabric for insertion in tires which comprises weaving an endless tube, imparting, during the weaving operation, different tensions to threads running longitudinally of the tube, and dividing the tube longitudinally whereby two strips similarly curved transversely are obtained.

5. The process of manufacturing a fabric for tires which comprises weaving an endless tube, imparting, during the weaving operai tion, different tensions to the war threads running longitudinally of the inner alf of the tube, the tension decreasing successively from the sides of the inner half of the tube toward the central portion of said inner half, and separating the inner half of said tube from the outer half whereby two strips of similar transverse curvature are obtained.

6. The method of manufacturing a curved fabric, which consists in weaving a tube and imparting different tensions to the threads running longitudinally of the same, the said threads running through each half of the tube being subjected to constantly decreasing tensions from the edge of each half to the middle of the same.

7. The method of manufacturing a curved fabric, which consists in weaving a tube and imparting a progressively increasing tension to the threads running longitudinally of the top, the threads at the middle of the top half being under least tension and the threads at the middle of the lower half being also under least tension, and the intermediate threads being subjected to progressively increasing tension away from said middle threads to the line midway between the same.

ln testimony whereof I have hereunto set my hand in presence of two subscribing witnesses this 7 th day of October 1907.

ERNST HERKNER.

Witnesses:

HENRY HAsPER, PAUL GREINER. 

